20 



HYDROCYANIC-ACID GAS FUMIGATION IN CALIFORNIA. 



have used lampblack and turpentine, or a soft, flexible paint, with 

 satisfaction. The first fine marked should be the one running 

 through the center of the tent. TVhen mam- tents are to be prepared, 

 the use of a stencil large enough to include a complete line of figures 

 on one side will facilitate the operation. The numerals should be 

 not less than 5 or 6 inches long. 



a 



( 



1 1 



Li 



- ,1 



! 



POLES AND DERRICKS. 



Two wooden poles or derricks are used in placing tents over trees. 

 Xo absolute statement can be made as to when poles should be 

 employed or when derricks. The practice is to use poles when- 



ever possible. 

 This has resulted, 

 in general, in the 

 use of poles with 

 tents up to 45 feet 

 in size and of 

 derricks with the 

 larger sizes. Some- 

 times poles are 

 used with tents of 

 48-foot or 50-foot 

 sizes, but this is 

 difficult, especially 

 if the trees are tall 

 and narrow rather 

 than low and 

 broad. Preferably 

 the poles should 

 be 6 inches to a 

 foot longer than 

 the height of the 

 trees. The two 

 lengths of poles in most common use are 14 feet and 16 feet. Twenty- 

 foot poles are occasionally required. These poles average from 2 inches 

 to 2\ inches in diameter, are rounded, and made of straight-grained 

 Oregon pine. The lower end is slightly sharpened to secure a ready 

 hold in the ground. The upper end, to which a rope is attached for 

 erecting the poles, preferably is also bluntly narrowed after one of 

 the methods shown in figure 4. This figure also shows two convenient 

 methods of attaching the rope. The end of a is narrowed about one- 

 half inch on all sides for 3 or 4 inches. This allows it to slip easily 

 through the rings in tents. The rope is tied in a shallow furrow 6 or 

 7 inches distant from the end. In b the end of the pole is merely 

 rounded, while the rope occupies an auger hole through the center 



Fig. 4.— Ends of hoisting poles used in placing tents over trees: a, Used 

 with tents where rings are present: I, used with tents having no rings. 

 (Original.) 



